Senators gave first-round approval to a plan that would phase in a state income tax cut of three-quarters of a percentage point over the next five years. At the same time, Missouri’s sales tax would gradually rise half a point.

The plan includes an extra tax cut for low-income residents, and it seeks to boost tax collections from Internet sales and some out-of-state retailers. The bill’s sponsor says it could reduce state revenues by about $450 million when fully implemented.